[MIFOSX-259] ehcache integration

7 api end points were cached. Selected cache storage is ehcache in-memory store.

Cache configuration are described in the wiki page. Also one could find details about how to plugin memcached on the same wiki page.

Main wiki page : 
https://mifosforge.jira.com/wiki/display/RES/GSOC+2013+-+Distributed+Caching+support

Wiki page on cache manager integration : https://mifosforge.jira.com/wiki/display/RES/Plunging+in+different+cache+managers+to+spring+cache+storage

Jira issue : https://mifosforge.jira.com/browse/MIFOSX-259